code: def test_reversed_subgraph_hash():
      """
      A directed graph with no bi-directional edges should yield different subgraph hashes
      to the same graph taken with edge directions reversed if there are no hash collisions.
      Here we test a cycle graph which is the minimal counterexample
      """
      G = nx.cycle_graph(5, create_using=nx.DiGraph)
      nx.set_node_attributes(
          G, {n: str(n) for n in G.nodes()}, name="label"
      )
  
      G_reversed = G.reverse()
  
      h = nx.weisfeiler_lehman_subgraph_hashes(G, node_attr="label")
      h_reversed = nx.weisfeiler_lehman_subgraph_hashes(
          G_reversed, node_attr="label"
      )
  
      assert h != h_reversed
  
imports: import pytest
  import networkx
  from networkx.generators import directed
label_desc: Use image node_id 15 for calling a global function with example usage: test_reversed_subgraph_hash() without return types